Paper-carriage-feed mechanism of type-writers.



v T. E. BUSCHMANN. PAPER CARRIAGE EEED MECHANISM OF TYPE WEITEEs.

APPLICATION FILED FEB.2G,191O. I I

Patented June 13, 1911.

I v E /4/v/v7"az a y 665W E n Y I Arr)!- illdl'lhl a ime triso noanuenn nuscrnasnu, or crrnivrnrra, esaiaalvznssrenos TO THE FIRM or .wnnnnnnn Wrens vomvr. wiNKLHorEa' & JAElHQKH a. e., or sci-rotten, NEAR GHEMNITZ, GERMANY.

P'APER-CARRIAGEFEED MEGHANISTE 0F TYPEWRITER S.

assets.

Specification of Letters Ll'atent.

Patented case is, ten.

Application fi1ed-February 26, 1910. Serial No. 546,168.

To all whom it may concern:

Be it known that l, THEoDoR BUSCHMANN, mechanical engineer, a subject of the Emperor of Germany, residing at Neefestrasse 51, Ghcmnitz', Saxony, Germany, have invented new and useful lmprovcments in Paper-(larriageelleed Mechanism of 'lypell riters, of which the follow- .ing is a specificatio.

My invention relates to the paper carriage feed mechanism of typewriters.

The paper carriage of a typewriter moved intermittently in the following wcllknown manner: The paper carriage is constantly pulled to the right by a drawband but cannot move freely because it is prevented by a rack which meshes with a rigidly held pinion. This pinion and an escapement wheel are rigidly secured to a shaft which is mounted only so as to rotate in the machine frame, and the escapement wheel is locked y a device which after one stroke on a keypermlts the wheel to rotate only one tooth. Such locking and feeding devices most used heretofore have as their main characteristic a detent and a pawl which can be'moved in common crosswise to the teeth of the escape- .ment wheel. The detent can only make this one movement; the pawl, on the contrary,

also necessarv to first discna e the rack' from the teeth of the pinion when it was desired to bring the carriage to a predetermined place in its path.

An important object of my invention is to attain greater safe y of operation with materially simpler means than could be said to attach to even the latest types of feeding devices. This increased safety of operation is attained by means of the following im provements:-Firstly, the movable pawl is a small, light and by reason of its small size an exceedingly freely-movable body whose face coacting with the tooth of the escapement wheel comes into a position exactly radial to the wheel, while the pawl itself can be withdrawn from the wheel tooth in eX yactly the same radial directiombut, on the is driven by a moving tooth of the wheel,.

after the latter has been released by the detent, until the pawl strikes a rigid abutment and s the esca'pement Wheel. The detent and pawl. are then pushed back crosswise to the wheel, the pawl is disengaged from the tooth of the wheel, and, being pulled by a spring, returns into its original position. This engaging and advancing pawl in some forms of construction is movable like a slide tangentially to the escapement wheel; in other forms it is pivotally arranged as an ordinary paw. on a pivot mounted on the detent itself, or is on a dog rocker rigidly conni cted to the latter. Both arrangements are however unsuitable because the rigid abutments, which determine the path of the pawl, prevent the pawlfrom yielding in front of the ratchet Wheel teeth when the carriage is moved toward the left. For this purpose it was usually necessary to uncouple' the e pement wheel from. the rack gear, which ren cred a special device necessary. i. e. a carriage release device. It was i I j i other hand, when the escapement wheel is turned back, is adapted to disengage from the teeth thereof. Another important improvement is the arrangement of a brake which is connected to the devicewhich allows the paper carriage to come completely under the control of its draw spring when the tabulator is being used, so that the carriage can. no longer strike sharply against the tabulator abutments, but advances with an even and moderate speed in the righthand direction.

The advantages secured by the above mentioned devices for the manipulation of the machine are :(1) that when disengaging the pawl from the cscapcment wheel only .the friction between the vfaces of the two parts has to be overcome, so that the escapement wheel does not require to be pressed back as was formerly necessary; (2) that the escapement wheel can be rotated back over the pawl without theuse of any special device, and (3) that the brake moderates One illustrative embodiment of my invention is represented by way of example in the acoompanyingv drawlngs, wherein Figure l is a front elevation, the front wall of the hanger-bearing having been cut away; Fig. 2 is a section on the line A-B in! Fig. 1, as seen from'the right-hand side the machine; Fig. 3 is a plan view, the paper carriage together with its carrying railand guidingrail having been, removed; Fig. 4 1s. a view similar to Fig. 2 and shows the position of the several parts when the tabulat-ing: device is set in operation; Fig. 5 is an elevation showing particularly the any rangementof the pawl and itsabutmen'ts in the position ,ifWhen the 'detent engages with the escapement wheel, and Fig. 6 1s a general view of the same parts shown in Fig. 5 and is at the same time an elevation of part of the device as shownin Fig. 4.

In order that my improved mechanism may be more easily understood, the wellknown parts of the feeding device are designated as follows 1 is the rack of the paper carriage, and '2 is the trough-shaped rail which is swung upward around the rod3 when the paper carriage is to be independent of the feeding device. The rack 1 is in constant mesh with a pinion4 mounted on a shaft 5, on which is also rigidly mounted the escapement wheel to which is attached a draw rod 14, this draw rod being' in connection with the universal bar and moving down when a key is de pressed. Thereupon-the upper end'of'the rocker 12 oscillates in the direction of the arrow :0 (Fig. 2) crosswise to the teeth of the escapement wheel, and brings the detent' 15, which is rigidly connected to the rocker 12, within reach of the teeth of the escapement wheel. The rocker '12 is returned in the direction of the arrow 3 up to the abutment pin 16 by a tension spring 17. The features of the mechanism which forms the subject-matter of my invention will now be described commencing with the pawl 18-. This pawl is mounted free to move upon the dog rocker 12 by means of a screw 19 on which it can both rotate and, owing to its longitudinal slot, be displaced in a longitudinal direction. The pawl 18 is constantly ulled upward and at the same time around to the left by means of a weak spring 20 attached to a downward extension of the pawl. When the ratchet wheel 6 presses the pawl 18 toward the right (Fig. 1) the latter'bears against the shaft of a screw 22, the head of a which on that side turned toward the pawl 18 is slightly beveled, to guide the pawl upon returning 't'o its normal position (Fig. 1) and to assist in holding it against the rocker 12. The head of the bolt is of such dimensions that whenthe pawl 18 is released by the ratchet wheel 6 it is still engaged by said head, as is shown in Fig. 5. As-is also I seen from the same figure,.the lower exten sion of the pawl 18 lies against an abutment which is constructed as an angle lever 23,24. The arm 24 is held elastically by means of a tight spring 25 against a rigid stop 26.

If the ratchet wheel 6 be now rotated clockwise,- the pawl 18 will first only move as far as the-lever arm 23, the teeth of the ratchet wheel will strike on the inclined face of the awl 18 and force the latter to yield still arther, and then the stop 23 which is elas- A pin 27 projecting-from the lower extension of the pawl 18 serves for this purpose, said pin being influenced by an oscillating member 28 journaled betweentwo screws 29. This member is provided'on the left-hand side (Fig. 1) with a forwardly directed lever 30 and a lever 31 inclined upw'ardto the rear, the front end of thelatter being bent at an angle toward the center of the hangerbearing (Fig. l). A vertically upwardly extending draw rod 32 is pivotally connected to lever 30, the upper end of this rod being hook-shaped and suspended from the above mentioned rail 2 of the paper carriage. Consequently when the rail 2 is raised the draw rod 32 must follow, the member 28 and its levers 30, 31 are rotated, and the member 28 coacts with the pin 27 and withdraws the pawl 18 from the ratchet wheel 6. Then the carriage is free. When the 'tabulating device is being used it is necessary to release the carriage every time the text of the line is typed, in order that the carriage may reach the tabulating stops for writing the numbers; How this is effected by the mechanism according to my invention is shown in Fig. 4. Thetabulator rod 33 is provided with a plate 34 upon which rests the upper end of the lever 35, 36. This lever is fulcrumed at 37 on the support 8 and the lower arm of this lever coacts with the above mentioned lever 31, and simuladjusting screw 39 in a second lever 40, 41 pivotally supported intermediate its ends. This lever when actuated, presses a leathercovered brake disk 42 in the direction of shaft 5 against, the enlarged'face 43 of the pinion 4. This arrangement very effectively prevents the shaft 5 jamming and bending, and also prevents any tendency which its taneously by means of the lug 38 with the centering set screws may have toward assumingan inclined position. Moreover, the

screw 39 provides a meansfor'altering the brake power as desired. As mentioned above, the operation of the device will be understood from Fig. 4..

' W hen the tabulator rod 33 has been rotatedclockwise and has rotated the" lever 35 a smalhdistance about its fulcrumf37, the- -10.

- 0f the-bridge lever attachment 31 and the lever arm 36 exerts pressure on thebe'n't end bridge 28' disengages the pawl 18f'from the ratchet wheel 6 by means of the pin 27." At

the same time the attachment 38 strikes the adjustin escrewf39"of the leverg tt), 41 andpresses t e braking plate 42 against the face 2 43. By this means the brake powerisappliede' to-"the pinion/l, and consequently to the paper'carriage, while. the escapenient wheel is released; The. carriage therefore travels at an equal and constant speed against the tabul'ator stop; Fig. 6 shows the pawl 18 Withdrawn from the teeth of the escapement "wheel6. I v

I'claime- 4 v i; 1. In feeding mechanism for .paper ear riages of typewriters,the combinatiomfwith;

the. frame and 'an escapement wheel jouron. said' rocker, a f spring-controlled 'vpawl. 2 mounted on said rockeran'd normally-coacting with said wheel, said awl being'mount-- ed to rotateand movera ially relatively to naled therein, .ofa dog rocker mounted in said frame, a. spring-pulled lever fulcrumed said wheel out of engagement therewith, and having an extension adapted to coact with said lever, and an abutment for holding said,

' 1 pawl in its normal position. I

2. In feeding mechanism for paper car- 'riages of typewriters, the combination, with the frame and an escapement wheel '3' ournaled therein, of a dog rocker, carrying a detent, mounted to rock in said frame,ja springpulled lever fulcrumed on said rocker, a spring-controlled pawl mounted on said .rocker and normallv coacting, with said wheel, said .pawl being. mounted to rotate and move radially relatively to said wheel out of engagement therewith, andhaving an extension adapted to coact with said lever,

and an abutment for holding saidpawl in its normal position; means for mov ng said pawl radially out of engagement with said wheel, and means operated by the latter means for braking said escapement wheel.

3. In feeding mechanism for paper carriages of typewriters, the combination, with the frame, and a shaft, carrying an escape;

ment wheel and a pinion, pivoted therein, ofv

mechanismcompr sing a pawl and-'apdetent for controlling said escapement :wheel, a"-

brake, a lever" operatively, connected with fsaidbrake, and a s econd lever for. a'ctuatin v the first mentioned; lever and applying :sai' braketo said pinion.

4. In feeding mechanism for paper carriages of typewriters, the combination, with the frame, and a shaft, carrying an escapement Wheel and'a pinion, pivoted therein,- of mechanism comprising a pawl anda detent for controlling said esca ement wheel,

.a' brake, a lever,,,having an'a ]ustable member-associated therewith, operativelyconnected with'said brake, and 'asecond lever adapted to coact with'said member to actuate said first mentioned lever to apply said.

brake to said pinion.

5. In feeding mechanism for paper carriages vof typewriters,.the combination, with the frame-and an escapement wheel journaled therein, of a dog rocker mounted in said frame,'a spring ul-led lever fulcrumed on saidrocker, a spring-controlled paw1'mount.-

ed ons'aid rockenand-normally coacting with'sa-id wheel, said pawl being. able to ro-i tate and moveradial yrelativelyto nsa-id wheel out of engagement therewith-,jand having an extension adapted to coact with said lever,-"and anabutment for holding said 'raronoa EUGEN BUSCHMANN.

Witnesses WM. J. KAU ETBUY, M. W. BRUNSWICK. 

